Toxins 2016, 8(1), 7; https://doi.org/10.3390/toxins8010007
Chemical Characterization and in Vitro Cytotoxicity on Squamous Cell Carcinoma Cells of Carica Papaya Leaf Extracts
1
School of Pharmacy, The University of Queensland, Brisbane, QLD 4072, Australia
2
Metabolomics Australia, Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, Brisbane, QLD 4072, Australia
*
Author to whom correspondence should be addressed.
Academic Editor: Carmela Fimognari
Received: 26 October 2015 / Revised: 14 December 2015 / Accepted: 18 December 2015 / Published: 24 December 2015
(This article belongs to the Special Issue Dietary and Non-Dietary Phytochemicals and Cancer)
Abstract
In traditional medicine, Carica papaya leaf has been used for a wide range of therapeutic applications including skin diseases and cancer. In this study, we investigated the in vitro cytotoxicity of aqueous and ethanolic extracts of Carica papaya leaves on the human oral squamous cell carcinoma SCC25 cell line in parallel with non-cancerous human keratinocyte HaCaT cells. Two out of four extracts showed a significantly selective effect towards the cancer cells and were found to contain high levels of phenolic and flavonoid compounds. The chromatographic and mass spectrometric profiles of the extracts obtained with Ultra High Performance Liquid Chromatography-Quadrupole Time of Flight-Mass Spectrometry were used to tentatively identify the bioactive compounds using comparative analysis. The principal compounds identified were flavonoids or flavonoid glycosides, particularly compounds from the kaempferol and quercetin families, of which several have previously been reported to possess anticancer activities. These results confirm that papaya leaf is a potential source of anticancer compounds and warrant further scientific investigation to validate the traditional use of papaya leaf to treat cancer. View Full-TextKeywords:
Carica papaya; cytotoxicity; mass spectrometry; cancer; flavonoids; chromatography
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Nguyen, T.T.; Parat, M.-O.; Hodson, M.P.; Pan, J.; Shaw, P.N.; Hewavitharana, A.K. Chemical Characterization and in Vitro Cytotoxicity on Squamous Cell Carcinoma Cells of Carica Papaya Leaf Extracts. Toxins 2016, 8, 7.
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